PYGOPODES. COL YMBIDJF, par excellence, since they possess this power in a most
C olymbus g la c ia lis (Linnaeus*).
THE GREAT NORTHERN DIVER.
Colymbus glacialis.-
Colymbus, Linnceusf.—Bill about as long as the head; strong, straight,
rather compressed, pointed. Nostrils basal, lateral, linear, perforate. Legs
thin, the tarsi compressed, placed very far backwards, and closely attached to
the posterior part of the body; toes three in front, united by membranes, one toe
behind, with a small membrane, articulated upon the tarsus; the claws flat.
Wings short, the first primary quill-feather the longest. Tail short and rounded.
Of the genus Colymbus, which is confined to the Northern
Hemisphere, there are three British species, called Divers,
* Syst. Nat. Ed. 12, i. p. 221 (1766).
t Tom. cit. p. 220. Linnseus included in his genus the Guillemots and the
Grebes.
marked and perfect degree. Except during their breeding-
season all the Divers live chiefly at sea, where they obtain
their living by following or keeping in the vicinity of shoals
of herrings, sprats, and other species of fishes of moderate
size, which they catch with great ease and certainty while
diving. They remain under water a very considerable time
without any apparent inconvenience, and have been taken,
while thus submerged, by a baited hook, and in the meshes
of nets.
Of these three, the Great Northern Diver, frequently
called the Immer—or Ember—Goose, is the largest in size,
and is of regular occurrence in our waters; but young birds
are much commoner than matured examples. The former
come closer to the shore and are more easily obtained ; but
the old birds keep, as a rule, to the open portions of the
sea, and even when seen are so wary that they seldom allow
of a near approach. There are, however, exceptions ; for
instance, in the winter of 1854 an adult Northern Diver
unexpectedly made its appearance in the very middle of the
inland county of Wiltshire, where it was first observed
swimming majestically to and fro on a pond at Spye Park,
and was afterwards caught in a ditch ; and other occurrences
of a similar nature are on record.
This species is sometimes very abundant on the coasts of
Cornwall and Devon, and throughout the open sea at the
mouth of the Channel; adults being more frequently observed
there than in the narrower waters, or on the east
coast. Mr. Gatcombe informs the Editor that on one occasion,
towards the end of winter, he counted no less than
thirty birds, apparently in pairs, in Plymouth Sound ; and
during the winter of 1874-75 they were unusually numerous.
In October, and again in spring, birds in full breeding-dress
are sometimes observed on the coasts of England; and in
Scotland, especially on the western side, they are not unfrequent.
Mr. R. Gray says that this Diver is abundant in
the Outer Hebrides at all seasons of the year, except the
month of July, and a few remain in Benbecula all the
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